Facsimile communication system

ABSTRACT

Pixel information and control information transmitted by a facsimile machine  1   a  is received by a procedure controlling circuit  13  having a MODEM  13   a  for facsimile machines. A facsimile procedure controller  14  decodes the pixel information and the control information. A connection/transfer controller  15  edits the decoded information and produces a control packet and a pixel packet. The control packet and the pixel packet are output to a local area network (LAN)  4  via a LAN controller  17  and a LAN control circuit  18.  When receiving a facsimile, the control packet signal transmitted via the LAN  4  is converted into pixel control information by the connection/transfer controller  15,  and the pixel control information is supplied to the facsimile procedure controller  14.  The connection/transfer controller  15  also converts the received pixel packet signal into pixel information. The pixel information is temporarily stored in a memory  16.  When a predetermined amount of pixel information is accumulated in the memory  16,  said predetermined amount of pixel information is supplied to the facsimile procedure controller  14,  and finally transmitted to the facsimile machine  1   a  via the procedure control circuit  13.

BACKGROUND OF THE INVENTION

[0001] 1. Field of Invention

[0002] This invention relates to a facsimile communication apparatus forallowing a plurality of facsimile machines designed for generaltelephone networks to communicate with each other via a datacommunication network, such as a local area network (LAN), and to aprogram recording unit which stores a program used in the facsimilecommunication apparatus. This invention also relates to a facsimilecommunication apparatus for allowing a plurality of facsimile machinesto communicate with each other in real time via an Internet Protocolnetwork (referred to as an IP network) based on the IETF (InternetEngineering Task Force), and to a program recording unit storing aprogram for controlling the facsimile communication apparatus.

[0003] 2. Description of the Related Art

[0004]FIG. 1 illustrates a conventional facsimile communication systemusing a data communication network, such as an LAN. The transmissionside facsimile machine 1 is a G-3 facsimile machine designed for generaltelephone networks, which is categorized according to the T.30Recommendation standardized by the ITU-T (InternationalTelecommunications Union, Telecommunication Standardization Department).The facsimile machine 1 is connected to the facsimile communicationapparatus 10A via a telephone network 2. The facsimile communicationapparatus (i.e., the gateway) 10A converts the communication protocolbetween the telephone network 2 and the LAN 4. The LAN 4 is furtherconnected to another facsimile communication apparatus (i.e., gateway)10B, to which the receiving side facsimile machine 7 is connected via atelephone network 6. The facsimile machines 1 and 7 have the samestandard, and they can mutually transmit and receive image informationvia the telephone networks. The facsimile communication apparatus 10Bhas the same structure as the facsimile communication apparatus 10A, andthe explanation on it will be omitted.

[0005] As shown in FIG. 2, the facsimile communication apparatus 10A hasa terminal accommodation circuit 3 a, to which a plurality of facsimilemachines 1 a through 1 n are connected via the corresponding telephonelines 2 a, 2 b, . . . , 2 n of the telephone network 2. The terminalaccommodation circuit 3 a is connected to a switch circuit 3 b whichselects the line which is currently requesting a facsimile transmissionfrom among the telephone lines 2 a through 2 n. A CODEC 3 c is connectedto the switch circuit 3 b in order to terminate the selected line. TheCODEC 3 c is a encoder/decoder which converts analog signals receivedfrom the telephone line 2 a into digital signals, and which decodesdigital signals into analog signals in order to output data to thetelephone line 2 a.

[0006] The terminal accommodation circuit 3 a, the switch circuit 3 band the CODEC 3 c are connected to the CPU 3 e via a common bus 3 d. TheCPU 3 e controls the overall operations of the facsimile communicationapparatus 10A. A memory 3 f and a LAN control circuit 3 g are alsoconnected to the common bus 3 d. The memory 3 f temporarily storesdigitized information prior to transmitting the digitized information.The LAN control circuit 3 g performs data transfer in a packet format toand from another facsimile communication apparatus 10B via the LAN 4.

[0007] The facsimile machine 1 of FIG. 1 is connected to the facsimilemachine 7 via the telephone line 2, the facsimile communicationapparatus 10A, the LAN 4, the facsimile communication apparatus 10B, andthe telephone line 6, in that order. If pixel information is transmittedfrom the facsimile machine 1 a of FIG. 2 to the facsimile machine 7, thepixel data read by the facsimile machine 1 a from the original documentis encoded according to a prescribed coding rule. The encoded pixel datais modulated by, for example, a 9600 bps MODEM installed in thefacsimile machine 1 a to produce an analog signal in the voice frequencyband. The analog signal is transmitted to the facsimile communicationapparatus 10A through the telephone line 2 a. The CODEC 3 c of thefacsimile communication apparatus 10A samples the analog signal suppliedvia the telephone line 2 a based on a sampling signal of, for example, 8KHz, and converts the sampled analog signal into an 8-bit digital signalfor each sampling.

[0008] Thus, the analog signal is converted into a 64 Kbps digitalsignal by the CODEC 3 c, which is then read by the CPU 3 e via thecommon bus 3 d. The CPU 3 e edits the digital signal into a packet dataof a predetermined size, and temporarily stores the packet data in thememory 3 f. The packet data stored in the memory 3 f is read out by theLAN control circuit 3 g, and transmitted to the receiving side facsimilecommunication apparatus 10B via the LAN 4. In the facsimilecommunication apparatus 10B, the packet data received from the LANcontrol circuit 3 g is temporarily stored in a memory. Then, the storeddata is read out by a CPU corresponding to the CPU 3 e, and supplied toa CODEC corresponding to the CODEC 3 c, which converts the data into ananalog signal and outputs the analog signal to the facsimile machine 7via the telephone network 6. Thus, the analog signal transmitted fromthe facsimile machine 1 a is converted into a digital signal by theCODEC 3 c of the facsimile communication apparatus 10A, and transferredas a packet data to the receiving side facsimile communication apparatus10B via the LAN 4.

[0009] However, the conventional facsimile communication system hasseveral problems.

[0010] Because the transfer path of the LAN 4 is divided into aplurality of channels in order to transfer the data in a packet format,the transfer delay time of the packet data is not constant. In addition,if the traffic of the LAN 4 is heavy, the packet data may be lost halfway through the transmission path. For these reasons, the analog signalswhich are being decoded by the CODEC 3 c of the receiving side facsimilecommunication apparatus 10B may sometimes be interrupted and, as aresult, wrong data is received by the receiving side facsimile machine7.

[0011] Furthermore, although the inherent data transfer rate between thefacsimiles machines 1 a and 7 is, for example, 9600 bps, the data istransferred at 64 Kbps in the LAN 4, which is inefficient from thestandpoint of data transfer capacity.

SUMMARY OF THE INVENTION

[0012] Therefore, the object of the invention is to overcome theproblems in the prior art, and to provide a facsimile communicationsystem that can perform facsimile communication in an efficient mannerfrom the standpoint of data transfer capacity with little transfererrors.

[0013] In order to achieve the object, in the first aspect of theinvention, a facsimile communication apparatus comprises: facsimileprocedure controller that receives and transmits control information andpixel information from and to facsimile machines connected to thefacsimile communication apparatus according to a predeterminedprocedure; a first information converter that converts the controlinformation and the pixel information received from the facsimilemachines into a control packet signal and a pixel packet signal ofpredetermined formats; data transmitter/receiver that transmits thecontrol packet signal and the pixel packet signal produced by the firstinformation converter via a data communication network, and thatreceives a control packet signal and a pixel packet signal transmittedvia the data communication network; and a second information converterthat converts the control packet signal and the pixel packet signalreceived by the data transmitter/receiver into control information andpixel information which are to be output to a receiving side facsimilemachine. The facsimile communication apparatus may further comprise amemory which stores a predetermined amount of pixel packet signalsreceived by the data transmitter/receiver and which outputs the storedsignals to the second information converter when the predeterminedamount of signals are accumulated.

[0014] In the second aspect of the invention, a facsimile communicationapparatus comprises: means for calling the receiving side facsimilemachine based on a request for connection to the receiving sidefacsimile machine as received from the data communication network; meansfor temporarily storing the image data transmitted from the transmissionside facsimile machine via the data communication network in a memory;means for starting transmission of the image data to the receiving sidefacsimile machine when a data-receiving control signal representing theacceptability of image data is received from the receiving sidefacsimile machine, provided that a desirable amount of image data isstored in the memory at the time of receipt of the data-receivingcontrol signal; and waiting controller for transmitting a prescribedwait control signal to the receiving side facsimile machine in order tohave the receiving side facsimile machine stand by if the desirableamount of image data has not been stored in the memory at the time ofreceipt of the receiving control signal representing the acceptabilityof the image data from the receiving side facsimile machine.

[0015] In still another aspect of the invention, a program recordingunit for storing a program for controlling a facsimile communicationapparatus is provided. This program recording unit comprises: means forcausing the facsimile communication apparatus to call the receiving sidefacsimile machine based on a request for connection to the receivingside facsimile machine received from the data communication network;means for causing the facsimile communication apparatus to temporarilystore the image data transmitted from the transmission side facsimilemachine via the data communication network in the memory; means forcausing the facsimile communication apparatus to start transmitting theimage data to the receiving side facsimile machine when the facsimilecommunication apparatus receives a data-receiving control signal thatrepresents the acceptability of image data of the receiving sidefacsimile machine, provided that a desirable amount of image data isstored in the memory at the time of receipt of the data-receivingcontrol signal; and waiting controller for causing the facsimilecommunication apparatus to transmit a prescribed wait control signal tothe receiving side facsimile machine in order to have the receiving sidefacsimile machine stand by if the desirable amount of image data has notbeen stored in the memory at the time of receipt of the receivingcontrol signal representing the acceptability of the image data from thereceiving side facsimile machine.

[0016] The waiting controller comprise determination means fordetermining whether or not the receiving side facsimile machine canstand by, while maintaining a data reception mode, if the desirableamount of image data has not been accumulated in the memory at the timeof receipt of the data-receiving control signal. If it is determinedthat the receiving side facsimile machine can wait in the data receptionmode, then waiting means causes the facsimile communication apparatus towait for further storage of image data until the desirable amount ofimage data is stored in the memory. On the other hand, if it isdetermined that the receiving side facsimile machine is not able to waitin the data reception mode, wait control signal transmitter causes thefacsimile communication apparatus to transmit the wait control signal tothe receiving side facsimile machine.

[0017] The desirable amount of image data stored in the memory can becalculated by multiplying the transmission rate of the image datadetermined by negotiation between the transmission side facsimilemachine and the receiving side facsimile machine by a predetermined timestored in advance. Alternatively, the desirable amount of image data canalso be calculated by multiplying the communication rate determined bynegotiation between the transmission side facsimile machine and thereceiving side facsimile machine by a predetermined time stored inadvance. The transmission side facsimile machine and the receiving sidefacsimile machine are G3 facsimile machines categorized based on theT.30 Recommendation. In this case, the data-receiving control signal isa data-receivable state confirmation signal CFR according to the T.30Recommendation, and the wait control signal is a transmission siteidentification signal TSI according to the T.30 Recommendation.

[0018] The contents of patent application H9-131812 filed in Japan onMay 22, 1997 and a patent application filed in Japan on Apr. 22, 1998,the application number is not yet assigned, are incorporated hereinto byreference.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Other features and objects will be apparent from the followingdetailed description with reference to the attached drawings, wherein:

[0020]FIG. 1 illustrates a conventional facsimile communication system;

[0021]FIG. 2 is a hardware block diagram of a conventional facsimilecommunication apparatus;

[0022]FIG. 3 is a hardware block diagram of the facsimile communicationapparatus according to a first embodiment of the invention;

[0023]FIG. 4 shows an example of control sequence of the facsimilecommunication apparatus of the first embodiment;

[0024]FIG. 5 shows an example of control sequence of the facsimilecommunication apparatus, which follows the control sequence shown inFIG. 4;

[0025]FIG. 6 is a hardware block diagram of the facsimile communicationapparatus according to a second embodiment;

[0026]FIG. 7 shows the facsimile communication sequence according to athird embodiment of the invention;

[0027]FIG. 8 is a flowchart showing the operation of the facsimilecommunication apparatus 10B according to a fourth embodiment; and

[0028]FIG. 9 is a hardware structural diagram of the facsimilecommunication apparatus according to the fourth embodiment of theinvention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0029] 1. First Embodiment

[0030]FIG. 3 illustrates the facsimile communication apparatus 10Aaccording to the first embodiment of the invention. The facsimilecommunication apparatus 10B has the same structure. The basic structureof the entire communication system that involves the facsimilecommunication apparatus 10A and a plurality of facsimile machines is thesame as that shown in FIG. 1, and the explanation will be omitted. Aplurality of G3 facsimile machines 1 a through 1 n, which arestandardized according to ITU-T Recommendation T.30, are connected tothe facsimile communication apparatus 10A via the correspondingswitchboard telephone lines 2 a through 2 n. The facsimile machine 1 areads pixel data from the original, and encodes it according to aprescribed coding rule in order to create pixel information PINF, whichis then transmitted to a receiving side facsimile machine 7 via thetelephone network 2. The facsimile machine 1 a also receives the pixelinformation PINF sent from another facsimile machine, and decodes it toreproduce the original pixel data and to output the transmitted image.In addition to the transfer of pixel data, the facsimile machine 1 atransmits and receives several types of control information CINF to andfrom other facsimile machines.

[0031] A part of the control information CINF is transferred as a tonesignal of, for example, 1850 Hz, while the rest of the controlinformation CINF and the pixel information PINF are transferred as, forexample, 9600 bps digital signals. The 9600 pbs digital signal ismodulated to produce a voice-band analog signal (of, for example, 1800Hz carrier frequency) by the MODEM built into the facsimile machine 1 a.This analog signal is transferred to and from the facsimilecommunication apparatus 10A via the telephone line 2 a.

[0032] The facsimile communication apparatus 10A has a terminalaccommodation circuit 11 for connecting a plurality of facsimilemachines 1 a through 1 n via the telephone switchboard lines 2 a through2 n. The terminal accommodation circuit 11 is connected to a switchcircuit 12, which selects the line that is requesting facsimiletransmission from among the telephone lines 2 a through 2 n. The switchcircuit 12 is connected to facsimile procedure controller (i.e., aprocedure control circuit 13 and a facsimile procedure controller 14),which terminates the selected line.

[0033] The procedure control circuit 13 has a modem 13 a which has thesame standard as the built-in modem of facsimile machine 1 a. The modem13 a demodulates the analog signal received from the telephone line 2 ato reproduce the original digital signal. The modem 13 a also modulatesthe digital signal addressed to the facsimile machine 1 a to produce ananalog signal, and outputs the analog signal to the telephone line 2 a.The procedure control circuit 13 is connected to the facsimile procedurecontroller 14 which executes the transfer control procedure according tothe Recommendation T.30, as in facsimile machine 1 a.

[0034] In other words, the facsimile procedure controller 14 decodes thecontrol information CINF, which was sent from the facsimile machine 1 aand received by the procedure control circuit 13. Then, the facsimileprocedure controller 14 produces response control information CINF, andsends it back to the facsimile machine 1 a via the procedure controlcircuit 13. The control information CINF and the pixel information PINFthat are to be transmitted to the addressed facsimile machine 7 areoutput from the facsimile procedure controller 14 to the firstinformation converter (i.e., the connection/transfer controller) 15.

[0035] The connection/transfer controller 15 edits the controlinformation CINF and the pixel information PINF supplied from thefacsimile procedure controller 14 into packets of predetermined formats,and produces a control packet signal CPKT and a pixel packet signal PCKTwhich are to be transmitted via the LAN 4. The connection/transfercontroller 15 is connected to a memory 16 for temporarily storing thegenerated control packet signal CPKT and pixel packet signal PCKT. Whenreceiving a facsimile from another facsimile machine, theconnection/transfer controller 15 functions as a second informationconverter. That is, during the receiving operation, the control packetsignal CPKT and the pixel packet signal PPKT sent via the LAN 4 are alsotemporarily stored in the memory 16. When the amount of received pixelpacket signal PPKT reaches a predetermined amount, theconnection/transfer controller 15 reads out said predetermined amount ofpixel packet signal PPKT, converts the pixel packet signal PPKT and thereceived control packet signal CPKT into pixel information PINF andcontrol information CINF, and output the pixel information PINF and thecontrol information CINF to the facsimile procedure controller 14.

[0036] A data transmitter/receiver (that is, a LAN controller 17 and aLAN control circuit 18) are also connected to the connection/transfercontroller 15. The LAN controller 17 controls a protocol, such as TCP/IP(Transport Control Protocol/Internet Protocol), for data transfer to andfrom the LAN 4. The LAN controller 17 is connected to the LAN controlcircuit 18 which is physically connected to the LAN 4 in order totransmit and receive control packet signals CPKT and pixel packetsignals PPKT.

[0037]FIG. 4 shows a part of the control sequence of the facsimilecommunication apparatuses 10A and 10B, according to the firstembodiment, up to transmission of a sheet of pixel information. Eachelement of the facsimile communication apparatus 10A is denoted by anumerical symbol and a suffix A, while each element of the facsimilecommunication apparatus 10B is denoted by a numerical symbol and asuffix B. First of all, when a call-out signal is sent from thefacsimile machine 1 a to the facsimile communication apparatus 10A viathe telephone line 2 a (S50), the terminal accommodation circuit 11Adetects the call-out, and informs the connection/transfer controller 15Aof the occurrence of call-out. The connection/transfer controller 15Ainstructs the LAN controller 17A to connect to the LAN 4. Then, the LANcontroller 17A transmits an address inquiry signal based on TCP/IP tothe LAN 4 (S52).

[0038] When a confirmation response signal is returned to the facsimilecommunication apparatus 10A via the LAN 4 (S54), the facsimilecommunication apparatus 10A transmits a connection request signal to thereceiving side facsimile communication apparatus 10B (S56). Based onthis connection request, the facsimile communication apparatus 10B callsthe addressed facsimile machine 7 via the telephone line 6, and outputsa call-in signal to the facsimile machine 7 (S58). When the facsimilemachine 7 responds to the call-in signal, a response signal istransmitted to the facsimile communication apparatus 10B (S60). Uponreceiving this response signal from the facsimile machine 7, thefacsimile communication apparatus 10B transmits a call-connectionresponse signal to the facsimile communication apparatus 10A via the LAN4 (S62). Upon receiving the call-connection response signal, thefacsimile communication apparatus 10A sends a response signal to thefacsimile machine 1 a (S64). At this point in time, the facsimilemachine 1 a is connected to the facsimile machine 7 via the telephoneline 2, the facsimile communication apparatus 10A, the LAN 4, thefacsimile communication apparatus 10B, and the telephone line 6.

[0039] Then, the receiving side facsimile machine 7 successivelytransmits a non-standard function signal NSF, a called siteidentification signal CSI, and a digital identification signal DIS,which are portions of control information CINF, based on the ITU-TRecommendation T.30 (S66). The facsimile procedure controller 14B of thefacsimile communication apparatus 10B receives and decodes thesesignals, and supplies the decoded signals to the connection/transfercontroller 15B. The connection/transfer controller 15B edits thesesignals into a control packet signal CPKT (NSF/CSI/DIS), and transmitsthe control packet signal to the LAN 4 via the LAN controller 17B andthe LAN control circuit 18B (S68).

[0040] In the transmission side facsimile communication apparatus 10A,the LAN control circuit 18A receives the control packet signal CPKT(NSF/CSI/DIS) sent via the LAN 4, and outputs this control packet signalto the connection/transfer controller 15A via the LAN controller 17A.The connection/transfer controller 15A decomposes the control packetsignal (NSF/CSI/DIS) into three type of control information CINF,namely, a non-standard function signal NSF, a called site identificationsignal CSI, and a digital identification signal DIS. Then, thenegligible non-standard function signal NSF is abandoned, while thecalled site identification signal CSI and the diaital identificationsignal DIS are output to the facsimile procedure controller 14A.

[0041] The facsimile procedure controller 14A controls the procedurecontrol circuit 13 so that it transmits the called site identificationsignal CSI and the digital identification signal DIS, which comprisecontrol information CINF, to the transmission side facsimile machine 1 avia the telephone line 2 (S70). Upon receiving the called siteidentification signal CSI and the digital identification signal DIStransmitted from the receiving side facsimile machine 7, the facsimilemachine 1 a outputs a transmission site identification signal TSI and adigital command signal DCS, which are control information CINF (S72).

[0042] When the control information CINF, which contains thetransmission site identification signal TSI and the digital commandsignal DCS, is received by the facsimile communication apparatus 10A viathe telephone line 2, these signals are edited into a control packetsignal CPKT (TSI/DCS), which is then transmitted to the facsimilecommunication apparatus 10D via the LAN 4 (S74). The facsimilecommunication apparatus 10B decomposes the received control packetsignal CPKT (TSI/DCS) into a transmission site identification signal TSIand a digital command signal DCS, and successively transmits thesesignals to the facsimile machine 7 via the telephone line 6 (S76). Atthis point in time, a facsimile communication link is establishedbetween the facsimile machines 1 a and 7.

[0043] After the facsimile communication link is established, thetransmission side facsimile machine 1 a transmits a training checksignal TCF, which is control information CINF for training thepixel-information receiving modem 13 a, to the facsimile communicationapparatus 10A (S78). The training check signal is used only in theanalog-signal section, and it is not necessary for the LAN 4.Accordingly, when the training of the modem 13 a of the procedurecontrol circuit 13A is completed, the modem 13 a returns a confirmationreturn signal CFR, which is control information CINF and informs of thefact that the modem 13 a is ready to receive the pixel information, tothe facsimile machine 1 a (S80). The same operation is performed in thereceiving side facsimile communication apparatus 10B. The modem 13 a ofthe procedure control circuit 13B sends a training check signal TCF tothe facsimile machine 7 (S82). When the training of the modem of thefacsimile machine 7 is completed, the facsimile machine 7 returns aconfirmation response signal CFR to the facsimile communicationapparatus 10B (S84). At this time, the facsimile machine 1 a startstransmitting the pixel information PINF.

[0044] The pixel data read by the facsimile machine 1 a is encodedaccording to the coding rule based on the recommendation T.30 to createpixel information PINF. The produced pixel information PINF is modulatedto produce an analog signal of the voice band by the 9600 bps modembuilt into the facsimile machine 1 a, and this analog signal istransmitted to the facsimile communication apparatus 10A via thetelephone line 2 (S86). The received analog signal is demodulated intodigital form by the modem 13 a of the procedure control circuit 13. Thisdemodulated pixel information PINF is supplied to theconnection/transfer controller 15A via the facsimile procedurecontroller 14A, converted into a pixel packet signal PPKT, andtransmitted to the LAN 4 via the LAN controller 17A and the LAN controlcircuit 18A (S88).

[0045] The pixel packet signal PPKT sent via the LAN 4 is received atthe LAN control circuit 18B and the LAN controller 17B of the facsimilecommunication apparatus 10B, and is supplied to the -connection/transfercontroller 15B. The connection/transfer controller 15B converts thepixel packet signal PPKT into pixel information PINF, and temporarilystores the pixel information PINF in the memory 16B. When the amount ofpixel information PINF accumulated in the memory 16B reaches apredetermined amount (for example, a data amount corresponding to apage), that amount of pixel information PINF is read out by thefacsimile procedure controller 14B, and is transmitted to the receivingside facsimile machine 7 by the procedure control circuit 13B via thetelephone line 6 (S90).

[0046]FIG. 5 shows the communication sequence following the sequence ofFIG. 4 (that is, after the completion of transmission of a page of pixelinformation from the facsimile machine 1 a). When the transmission sidefacsimile machine 1 a has transmitted a page of pixel information PINF,it generates a multi-page signal MPS, which is control information CINF(S92). The facsimile procedure controller 14A of the facsimilecommunication apparatus 10A decodes this control information CINF, andoutputs the decoded signal to the communication/transfer controller 15A.The communication/transfer controller 15A edits the multi-page signalMPS into a control packet signal CPKT (MPS), and outputs the controlpacket signal CPKT (MPS) to the LAN 4 via the LAN controller 17A and theLAN control circuit 18A (S94).

[0047] This control packet signal CPKT (MPS) sent via the LAN 4 isreceived at the LAN control circuit 18B and the LAN controller 17B ofthe facsimile communication apparatus 10B, and is supplied to thecommunication/transfer controller 15B. The communication/transfercontroller 15B converts the received control packet signal CPKT (MPS)into a multi-page signal MPS, and outputs it to the facsimile procedurecontroller 14B. This multi-page signal MPS is output from the facsimileprocedure controller 14B to the receiving side facsimile machine 7 viathe procedure control circuit 13B and the telephone line 6 (S96). Uponreceiving the multi-page signal MPS, the facsimile machine 7 outputs amessage confirmation signal MCF, which is control information CINF, tothe facsimile communication apparatus 10B (S98).

[0048] The facsimile communication apparatus 10B edits the messageconfirmation signal MCF into a control packet signal CPKT (MCF), andtransmits it to the facsimile communication apparatus 10A via the LAN 4(S100). The facsimile communication apparatus 10A converts the receivedcontrol packet signal CPKT (MCF) into a message confirmation signal MCF,and transmits it to the facsimile machine 1 a via the telephone line 2(S102). Upon receiving the message confirmation signal MCF, thefacsimile machine 1 a starts transmitting the pixel data of the nextpage as the pixel information PINF in the same manner as the first pagewas transmitted.

[0049] When the facsimile machine 1 a is finished transmitting all thepixel information PINF, the facsimile machine 1 a outputs anend-of-procedure signal EOP, which is control information CINF (S110).The facsimile communication apparatus 10A edits this end-of-proceduresignal EOP into a control packet signal CPKT (EOP), and sends thecontrol packet signal CPKT (EOP) to the facsimile communicationapparatus 10B via the LAN 4 (S112). Upon receiving the control packetsignal CPKT (EOP), the facsimile communication apparatus 10B convertsthis packet signal into an end-of-procedure signal EOP, and sends it tothe receiving side facsimile machine 7 via the telephone line 6 (S114).When the facsimile machine 7 receives the end-of-procedure signal EOP,it returns a message confirmation signal MCF (S116-S120).

[0050] When the facsimile machine 1 a receives the message confirmationsignal MCF from the facsimile machine 7, it generates a disconnectioncommand signal DCN, which is control information CINF (S122) Thefacsimile communication apparatus 10A edits the disconnection commandsignal DCN into a control packet signal CPKT (DCN), and transmits it tothe facsimile communication apparatus 10B via the LAN 4 (S124). Thefacsimile communication apparatus 10B converts the control packet signalCPKT (DCN) into a disconnection command signal DCN, and sends it to thereceiving side facsimile machine 7 via the telephone line 6 (Sl26). Atthis point of time, facsimile communication between the facsimilemachines 1 a and 7 is finished.

[0051] After finishing the communication, the facsimile machines 1 a and7 disconnect themselves from the telephone lines 2 and 6, respectively(S128). These disconnected states are reported to the facsimilecommunication apparatuses 10A and 10B, whereby the facsimilecommunication apparatuses 10A and 10B disconnect themselves from the LAN4 (S130). As has been described above, each of the facsimilecommunication apparatuses 10A and 10B has a procedure control circuit 13having a modem 13 a, which is the same standard as the facsimile machine1 a, and a facsimile procedure controller 14 which executes a transfercontrol procedure according to the recommendation T.30.

[0052] These elements allow the control information CINF and the pixelinformation PINF to be transferred between the facsimile machine 1 a andthe facsimile communication apparatus 10A according to the facsimileprocedure, and they also allow the control packet signal CPKT and thepixel packet signal PPKT to be transferred between the facsimilecommunication apparatuses 10A and 10B according to the procedure of theLAN 4. Transmitted data is temporarily stored in the memory, and apredetermined amount of data is output to the receiving side facsimilemachine. Thus, facsimile communication is achieved via datacommunication networks, such as the LAN 4, with little transmissionerrors and by efficiently using transfer capacity.

[0053] 2. Second Embodiment

[0054]FIG. 6 is a hardware block diagram of the facsimile communicationapparatus 10A according to the second embodiment of the invention. Thefacsimile communication apparatus 10B also has the same structure asthat shown in FIG. 6. In this embodiment, the facsimile communicationapparatus 10A has a CPU 37 in place of the facsimile procedurecontroller 14, the LAN controller 17, and the communication/transfercontroller 15. The facsimile communication apparatus 10A also has aCD-ROM driver 34 for reading out a program from a CD-ROM 36, and a harddisc drive 38 for storing the program read out from the CD-ROM 36. Theprogram stored in the hard disc drive 38 is read out by the memory 16,and is executed. In this specification and in the appended claims,portable recording media including the CD-ROM 36, fixed storingapparatuses including the hard disc drive 38, and volatile storingdevices including the memory 16 are all referred to as program recordingunits.

[0055] The program stored in the program recording unit may be executeddirectly by the CPU 37, or it may be decoded prior to being executed bythe CPU 37 if it is stored in an encoded format. The program stored inthe CD-ROM 36 has program modules for causing the CPU 37 to execute theoperations performed by the facsimile procedure controller 14, theconnection/transfer controller 15, and the LAN 4, shown in FIG. 3. Basedon these program modules, the CPU 37 performs the same operations as thefacsimile communication apparatus 10A shown in FIGS. 3 thru 5. In thisembodiment, the operations of the facsimile communication apparatus 10Acan be easily changed by simply changing the CD-ROM 36.

[0056] 3. Third Embodiment

[0057] In the third embodiment, an IP network (Internet Protocolnetwork) 50 according to the IETF (Internet Engineering Task Force) isused as the data communication network in place of the LAN 4 shown inFIG. 1. The “IP network” includes both the Internet and intranets. Thefacsimile communication apparatus 10A according to this embodiment hasan IP network control circuit and an IP network controller in place ofthe LAN control circuit 18 and the LAN controller 17 shown in FIG. 3.The other hardware structure is the same as that shown in FIG. 3, andthe explanation will be omitted.

[0058]FIG. 7 shows a part of the control sequence of the facsimilemachine 1 a, according to the third embodiment, up to transmission of asheet of pixel information to the facsimile machine 7. The facsimilemachines 1 a and 7 are connected to the facsimile communicationapparatuses 10A and 10B via the telephone lines 2 and 6, respectively,as in the first embodiment. when the facsimile communication apparatus10A receives a request for connection to the facsimile machine 7 fromthe facsimile machine 1 a (S200), the facsimile communication apparatus10A accesses the address information storing device 16 (S202) to obtainthe IP address of the facsimile communication apparatus 10B, to whichthe facsimile machine 7 is connected (S204). Then, the facsimilecommunication apparatus 10A requests the facsimile communicationapparatus 10B to connect itself to the facsimile machine 7 (S206). Inresponse to this request, the facsimile communication apparatus 10Bconnects itself to the facsimile machine 7 (S208 and S210). Upon theestablishment of the connection between the facsimile communicationapparatus 10B and the facsimile machine 7, the facsimile communicationapparatuses 10A and 10B cooperate to provide a communication pathbetween the facsimile machines 1 a and 7.

[0059] As in the first embodiment, when the facsimile machine 1 areceives a connection response signal (S212 and S214), followed by anon-standard function signal NSF, a called site identification signalCSI, and a digital identification signal DCS (S216 through S220), fromthe facsimile machine 7 via the facsimile communication apparatuses 10Aand 10B, the facsimile machine 1 a transmits a transmission siteidentification signal TSI, a digital command signal DCS, and a trainingcheck signal TCF (S222). Then, upon receiving a receipt-readyconfirmation signal CFR from the facsimile communication apparatus 10A(S224), the facsimile machine 1 a starts transmitting the pixel data(S230). Prior to this, the facsimile communication apparatus 10Atransfers the transmission site identification signal TSI and thedigital command signal DCS to the facsimile communication apparatus 10B(S226) upon transmitting the receipt-ready confirmation signal to thefacsimile machine 1 a (S224).

[0060] While the facsimile machine 1 a is transmitting the pixel data(S230), the receiving side facsimile communication apparatus 10B and thefacsimile machine 7 are transferring control signals to each other (S228and S234 through S242). In other words, the receiving side facsimilecommunication apparatus 10B stores the pixel data sent from thefacsimile machine 1 a via the facsimile communication apparatus 10A inthe memory 3 f, while it transfers control signals to and receivescontrol signals from the facsimile machine 7 (S232).

[0061] The facsimile communication apparatus 10B starts transferring thepixel data to the facsimile machine 7 after a predetermined amount ofpixel data has been stored in the memory (S246) in order to avoidundesirable interruption of the communication between the facsimilemachines 1 a and 7, which generally occurs due to a transfer delayarising in the IP network 50. Prior to this, if a predetermined amountof data has not been accumulated in the memory when the facsimilecommunication apparatus 10B receives the receipt-ready confirmationsignal CFR (S242), the negotiation sequence—that is, transmission of thetransmission side identification signal TSI, the digital command signalDCS, and the receipt-ready confirmation signal CFR to the facsimilemachine 7 (S230 through S242)—is repeated in order to gain time forfurther accumulation of pixel data in the memory 3 f.

[0062] According to the third embodiment, the facsimile communicationapparatus 10B can start transmission of pixel data after a sufficientamount of pixel data is accumulated in the memory 3 f. Accordingly, evenif the communication rate of the IP network 50 drops due to an increasein traffic, the facsimile communication apparatus 10B can continuouslyconvert the pixel data read out from the memory 3 f into analog signalsand transmit them to the facsimile machine 7 at a constant rate. If thepixel data is lost, the lost data can be retransmitted to the facsimilecommunication apparatus 10A, during which the pixel data read out fromthe memory 3 f are continuously transmitted to the receiving sidefacsimile machine 7 without cutting off communication. Thus, thisarrangement can prevent an unexpected shutoff of the communicationbetween the facsimile communication apparatus 10B and the facsimilemachine 7 due to a decrease in communication rate or data loss.

[0063] 4. Fourth Embodiment

[0064] In the previous embodiment (i.e., the third embodiment), thefacsimile communication apparatus 10B stores a predetermined amount ofpixel data in the memory 3 f. However, if the communication rate betweenthe facsimile communication apparatus and the facsimile machine 7 isrelatively slow, it takes time to transmit the pixel data stored in thememory 3 f to the facsimile machine 7. In such a case, it is notnecessary to store a great amount of pixel data in the memory 3 f. Inview of this, too much pixel data in excess of a desirable amount mayoccasionally be accumulated in the memory in the third embodiment. Inaddition, a sequence lag which generally arises between the transmissionside facsimile machine 1 a and the receiving side facsimile machine 7becomes large and, as a result, a communication error is likely to occurin the transmission side facsimile machine 1 at a page boundary due toresponse wait time-out.

[0065] Furthermore, in the third embodiment, the facsimile communicationapparatus 10B repeats the negotiation sequence (S212 through S216) if apredetermined amount of pixel data has not been accumulated in thememory at the time of receipt of a CFR from the receiving side facsimilemachine 7. During this negotiation sequence, too much pixel dataexceeding the desirable amount is accumulated because the negotiationsequence generally takes time. This also causes a sequence lag betweenthe transmission side facsimile machine 1 a and the receiving sidefacsimile machine 7, and the time when the receiving side facsimilemachine 7 has fully received a page of pixel data is delayed. As aresult, a communication error may occur at a page boundary in thetransmission side facsimile machine 1 a due to response wait time-out.In order to overcome these problems, a real-time facsimile communicationsystem which can absorb a delay in the IP network and allow stable andhighly successful communication is provided in the fourth embodiment.

[0066]FIG. 8 shows the operation flow of the facsimile communicationapparatus 10B according to the fourth embodiment. The facsimilecommunication apparatus 10B has a standard hardware structure as in thethird embodiment. When the facsimile communication apparatus 10Breceives a request for connection to the facsimile machine 7 from thefacsimile communication apparatus 10A, it informs the facsimile machine7 of the occurrence of call-in, and connects itself to the facsimilemachine 7 (S300). Then, the facsimile communication apparatus 10B readsthe communication rate between the facsimile machines 1 and 7 from thecontrol signal DCS received from the facsimile machine 1 a, andcalculates the minimum amount of pixel data that must be stored in thememory in order to continuously transmit the pixel information to thefacsimile machine 7 for a predetermined period of time (S302). Then, thefacsimile communication apparatus 10B transmits a transmission siteidentification signal TSI, a digital command signal DCS, and a trainingcheck signal TCF to the facsimile machine 7 for the purpose ofcommunication training with the facsimile machine 7 (S304). When thefacsimile communication apparatus 10B receives pixel data from thefacsimile communication apparatus 10A (S306), it stores. the pixel datain the memory 3 f (S308).

[0067] If the facsimile communication apparatus 10B has already receiveda control signal CFR from the facsimile machine 7 (S310), it determinesif the minimum necessary amount of pixel data calculated in S302 hasbeen accumulated in the memory 3 f (S312) If so, the facsimilecommunication apparatus 10B starts transmitting the pixel data to thefacsimile machine 7 (S314). Meanwhile, the receiving side facsimilemachine 7 transmits a receiving-ready confirmation signal CFR, and if itdoes not receive any pixel data even after a predetermined period oftime T has passed since the transmission of the receiving-readyconfirmation signal CFR, it again transmits a non-standard functionsignal NSF according to the Recommendation T.30. The facsimilecommunication apparatus 10B stores the predetermined time T (from thetransmission of the receiving-ready confirmation signal CFR toimmediately before the transmission of the non-standard function signalNSF) in advance. If the minimum necessary amount of pixel data has notbeen accumulated in the memory in S312, the facsimile communicationapparatus 10B determines whether said predetermined time T has alreadyelapsed (S316).

[0068] If time T has not passed yet in S316, the process returns toS306, and the pixel data is continuously stored in the memory 3 f. Iftime T has already passed in S316, the facsimile communication apparatus103 sets a flag that represents the receiving sate of thereceiving-ready confirmation signal CFR to “No Receipt” (S318), and theprocess returns to the training sequence (S304). Accordingly to thisoperation flow, the communication procedure does not have to return tothe transmission of the non-standard function signal NFS, and thefacsimile machine 7 can start receiving the pixel data earlier.

[0069]FIG. 9 illustrates an example of software function of thefacsimile communication apparatus 10B according to the fourth embodimentof the invention. The facsimile communication apparatus 10B has anexecuting unit 22 a and a data unit 22 b as structural elements of thesoftware. The executing unit 22 a comprises an IP communicationcontroller (IPC) 30, an IP data analyzer (DAL) 31, a facsimilecommunication controller (FCL) 32, a pixel data storage controller (STM)33, and a timing controller (TQM) 34. The data unit 22 b comprises apixel data storage 40 and a pixel data storage amount manager 41. Thepixel data storage 40 stores pixel data information together with datarepresenting the current storage amount of pixel data. The pixel datastorage amount manager 41 stores the optimum transmission time that isconverted from the optimum storage amount of pixel data. The facsimilecommunication apparatus 10A has the same structure as the facsimilecommunication apparatus 10B, and further explanation will be omitted.

[0070] The operation of the major elements of the receiving sidefacsimile communication apparatus 10B, which are performed during theoperation flow shown in FIG. 8, will be explained with reference to FIG.9. When the IP communication controller 30 receives IP data from thetransmission side facsimile communication apparatus 10A via the IPnetwork 50, it requests the IP data analyzer 31 to analyze the IP data.If the received IP data is a T.30 signal consisting of control signalsTSI and DCS as a result of the analysis, the IP data analyzer 31requests the facsimile communication controller 32 to send this IP datato the facsimile machine 7. The facsimile communication controller 32transfers the control signals TSI and DCS to the facsimile machine 7and, at the same time, it obtains from the DCS the communication rate ofthe facsimile communication which is to take place in this sequence, andreports the communication rate to the pixel data storage controller 33.

[0071] On the other hand, if the received IP data is pixel data, thenthe IP data analyzer 31 requests the pixel data storage controller 33 totemporarily store this IP data. In response to this request, the pixeldata storage controller 33 stores the IP data in the pixel data storage41 and, at the same time, it updates the storage amount information. Thepixel data storage controller 33 reads out the optimum data transmissiontime from the pixel data storage manager 41, calculates the optimumamount of pixel data that should be stored by multiplying thecommunication rate by the optimum transmission time, and stores thisoptimum value in the pixel data storage manager 41. When the facsimilecommunication controller 32 receives the CFR from the receiving sidefacsimile machine 7, it inquires of the pixel data storage controller 33as to whether or not the optimum amount of pixel data has already beenstored.

[0072] The pixel data storage controller 33 reads out the optimumpixel-data storage amount from the pixel data storage manager 41 and, atthe same time, it reads the amount of pixel data that has been stored inthe pixel data storage 40 by that point of time and compares it with theoptimum value. If the optimum amount of pixel data has already beenaccumulated, the pixel data storage controller 33 informs the facsimilecommunication controller 32 that the pixel data can now be transmitted.The facsimile communication controller 32 requests the pixel datastorage controller 33 to read out the pixel data, and it startstransferring the pixel data to the facsimile machine 7. On the otherhand, if the optimum amount of pixel data has not been accumulated inthe comparison step, then the facsimile communication controller 32instructs the timing controller 34 to restart the facsimilecommunication controller 32 after a predetermined time interval, and theprocess is interrupted.

[0073] The timing controller 34 restarts the facsimile communicationcontroller 32 after a predetermined time, and the facsimilecommunication controller 32 again inquires of the pixel data storagecontroller 33 as to whether the optimum amount of pixel data has beenaccumulated. These steps are repeated until the optimum amount of pixeldata has been accumulated in the data storage 40. During theinterruption, the facsimile communication controller 32 does nottransmit any signals or pixel data to the receiving side facsimilemachine 7.

[0074] If no pixel data is transmitted to the receiving side facsimilemachine 7, even after a predetermined period of time has passed sincethe transmission of the receiving-ready confirmation signal CFR, thefacsimile machine again transmits a non-standard function signal NSFaccording to the Recommendation T.30. The timing controller 34 stores inadvance the time T from the transmission of the receiving-readyconfirmation signal to immediately before the transmission of thenon-standard function signal NSF, and if time T has elapsed, it informsthe facsimile communication controller 32 of the time limit. Then, thefacsimile communication controller 32 restarts from the step oftransmitting a transmission site identification signal TSI to thereceiving side facsimile machine 7, and allows the pixel data to becontinuously stored. This operation flow can allow the receiving sidefacsimile machine 7 to finish receiving the pixel data earlier, ascompared with the case in which the process returns to theretransmission of the non-standard function signal NSF.

[0075] According to this embodiment, the minimum and necessary amount ofpixel data, which is determined by the communication rate negotiatedbetween the transmission side facsimile machine 1 a and the receivingside facsimile machine 7, is stored. This arrangement can prevent atransmission site identification signal TSI from being transmitted asmuch as possible before the minimum necessary amount of pixel data isaccumulated, even after the receipt of the receiving-ready confirmationsignal TSI. Consequently, accumulation of excessive amount of pixeldata, as well as communication errors due to inappropriate accumulationof pixel data, can be prevented. Thus, a stable and real-time facsimilecommunication can be achieved.

[0076] Although the present invention has been descried with referenceto the specific embodiments, the present invention is not limited tothese embodiments, and it will be apparent to those skilled in the artthat there are many changes and substitutions which can be made withoutdeparting from the scope of the invention. Examples of such changes andsubstitutions are listed below.

[0077] (a) Although the LAN 4 or the IP network 50 are used as datacommunication networks in the embodiment, other types of datacommunication networks can be used.

[0078] (b) The facsimile procedure controller 14, theconnection/transfer controller 15, and the LAN controller 17 have beendescribed as independent elements in the embodiment. However, theseelements may be realized as software executed by a single CPU. This canfacilitate the hardware structure of the facsimile communicationapparatus 10.

[0079] (c) Even if the facsimile machines 1 a and 7 employ non-standardprocedures which are not based on Recommendation T.30, continuous pixeldata transmission can be achieved, without interrupting the facsimilecommunication, by adjusting the pixel data transmission timing asdescribed in the embodiments.

[0080] Because the facsimile communication apparatus according to thefirst invention has a memory for temporarily storing a predeterminedamount of pixel packet signals received via a data communicationnetwork, stable facsimile communication can be maintained without anunexpected breakup in the middle of transmission, even if thedata-transfer rate differs between the transmission side facsimilemachine 1 a and the receiving side facsimile machine 7. In addition, amechanism for absorbing a delay in the UP network and for preventingexcessive amount of accumulation of pixel data is provided and,consequently, a facsimile communication system having a highcommunication success rate (with little communication error) can beachieved.

What is claimed is:
 1. A facsimile communication apparatus connected toa plurality of facsimile machines used in general telephone networks,each of the facsimile machines modulating pixel information and controlinformation to produce analog signals, said facsimile communicationapparatus comprising: facsimile procedure controller connected to saidplurality of facsimile machines for receiving the control informationand the pixel information from and transmitting the control informationand the pixel information to the facsimile machines according to apredetermined procedure; first information converter for converting thecontrol information and the pixel information transmitted from thefacsimile machines into a control packet signal and a pixel packetsignal of predetermined formats; data transmitter/receiver fortransmitting and receiving the control packet signal and the pixelpacket signal produced by the first information converter via a datacommunication network; and second information converter for convertingthe control packet signal and the pixel packet signal received by thedata transmitter/receiver into control information and pixel informationwhich is to be output to the facsimile procedure controller.
 2. Thefacsimile communication apparatus according to claim 1, furthercomprising memory for storing and accumulating the pixel packet signalreceived by the data transmitter/receiver and for outputting the storedpixel packet signal to the second information converter when the amountof stored pixel packet signal reaches a predetermined amount.
 3. Afacsimile communication apparatus for receiving image data from atransmission side facsimile machine via a data communication network,for temporarily storing the image data in a memory, and for transmittingthe image data to a receiving side facsimile machine, the facsimilecommunication apparatus comprising: means for calling the receiving sidefacsimile machine when it receives a request for connection to thereceiving side facsimile machine from the data communication network;means for receiving the image data from the transmission side facsimilemachine via the data communication network and for temporarily storingthe received image data in the memory; means for starting transmissionof the image data to the receiving side facsimile machine in response toreception of a data-receiving control signal representing theacceptability of image data from the receiving side facsimile machine,provided that a desirable amount of image data is stored in the memoryat the time of receipt of the data-receiving control signal; and waitingcontroller for transmitting a prescribed wait control signal to thereceiving side facsimile machine in order to have the receiving sidefacsimile machine stand by if the desirable amount of image data has notbeen stored in the memory at the time of receipt of the receivingcontrol signal representing the acceptability of the image data from thereceiving side facsimile machine.
 4. The facsimile communicationapparatus according to claim 3, wherein the waiting controllercomprises: determination means for determining whether or not thereceiving side facsimile machine can wait in a data reception mode ifthe desirable amount of image data has not been stored in the memory atthe time of receipt of the data-receiving control signal; waiting meansfor waiting for further storage of image data until the desirable-amountof image data is stored in the memory if the determination meansdetermines that the receiving side facsimile machine can wait in thedata reception mode; and wait control signal transistor for transmittingthe wait control signal to the receiving side facsimile machine if thedetermination means determines that the receiving side facsimile machinecan not wait in the data acceptable state.
 5. The facsimilecommunication apparatus according to claim 4, further comprisingcalculation means for calculating the desirable amount of image datastored in the memory by multiplying the transmission rate of the imagedata determined by negotiation between the transmission side facsimilemachine and the receiving side facsimile machine by a predetermined timestored in advance.
 6. The facsimile communication apparatus according toclaim 4, further comprising calculation means for calculating thedesirable amount of image data stored in the memory by multiplying thecommunication rate determined by negotiation between the transmissionside facsimile machine and the receiving side facsimile machine by apredetermined time stored in advance.
 7. The facsimile communicationapparatus according to claim 6, wherein the transmission side facsimilemachine and the receiving side facsimile machine are G3 facsimilemachines categorized based on a T.30 Recommendation, the data-receivingcontrol signal comprises a data-receivable state confirmation signal CFRaccording to the T.30 Recommendation, and the wait control signalcomprises a transmission site identification signal TSI according to theT.30 Recommendation.
 8. The facsimile communication apparatus accordingto claim 5, wherein the transmission side facsimile machine and thereceiving side facsimile machine are G3 facsimile machines categorizedbased on a T.30 Recommendation, the data-receiving control signalcomprises a data-receivable state confirmation signal CFR according tothe T.30 Recommendation, and the wait control signal comprises atransmission site identification signal TSI according to the T.30Recommendation.
 9. The facsimile communication apparatus according toclaim 4, wherein the transmission side facsimile machine and thereceiving side facsimile machine are G3 facsimile machines categorizedbased on a T.30 Recommendation, the data-receiving control signalcomprises a data-receivable state confirmation signal CFR according tothe T.30 Recommendation, and the wait control signal comprises atransmission site identification signal TSI according to the T.30Recommendation.
 10. The facsimile communication apparatus according toclaim 3, wherein the transmission side facsimile machine and thereceiving side facsimile machine are G3 facsimile machines categorizedbased on a T.30 Recommendation, the data-receiving control signalcomprises a data-receivable state confirmation signal CFR according tothe T.30 Recommendation, and the wait control signal comprises atransmission site identification signal TSI according to the T.30Recommendation.
 11. A program recording unit storing a program forcontrolling a facsimile communication apparatus that receives image datafrom a transmission side facsimile machine via a data communicationnetwork, temporarily stores the received image data in a memory, andtransmits the image data to a receiving side facsimile machine, saidprogram recording unit comprising: means for causing the facsimilecommunication apparatus to call the receiving side facsimile machinebased on a request for connection to the receiving side facsimilemachine received from the data communication network; means for causingthe facsimile communication apparatus to temporarily store the imagedata transmitted from the transmission side facsimile machine via thedata communication network in the memory; means for causing thefacsimile communication apparatus to start transmitting the image datato the receiving side facsimile machine when the facsimile communicationapparatus receives a data-receiving control signal that represents theacceptability of image data of the receiving side facsimile machine,provided that a desirable amount of image data is stored in the memoryat the time of receipt of the data-receiving control signal; and waitingcontroller for causing the facsimile communication apparatus to transmita prescribed wait control signal to the receiving side facsimile machinein order to have the receiving side facsimile machine stand by if thedesirable amount of image data has not been stored in the memory at thetime of receipt of the receiving control signal representing theacceptability of the image data from the receiving side facsimilemachine.
 12. The program recording unit according to claim 11, whereinthe waiting controller comprises: determination means for determiningwhether or not the receiving side facsimile machine can wait in a datareception mode if the desirable amount of image data has not been storedin the memory at the time of receipt of the data-receiving controlsignal; waiting means for waiting for further storage of image datauntil the desirable amount of image data is stored in the memory if thedetermination means determines that the receiving side facsimile machinecan wait in the data acceptable state; and wait control signaltransmitter for transmitting the wait control signal to the receivingside facsimile machine if the determination means determines that thereceiving side facsimile machine cannot wait in the data reception mode.13. The program recording unit according to claim 12, further comprisingcalculation means for calculating the desirable amount of image datastored in the memory by multiplying the transmission rate of the imagedata determined by negotiation between the transmission side facsimilemachine and the receiving side facsimile machine by a predetermined timestored in advance.
 14. The program recording unit according to claim 12,further comprising calculation means for calculating the desirableamount of image data stored in the memory by multiplying thecommunication rate determined by negotiation between the transmissionside facsimile machine and the receiving side facsimile machine by apredetermined time stored in advance.
 15. The program recording unitaccording to any of claims 14, wherein the transmission side facsimilemachine and the receiving side facsimile machine are G3 facsimilemachines categorized based on a T.30 Recommendation, the data-receivingcontrol signal comprises a data-receivable state confirmation signal CFRaccording to the T.30 Recommendation, and the wait control signalcomprises a transmission site identification signal TSI according to theT.30 Recommendation.
 16. The program recording unit according to any ofclaims 13, wherein the transmission side facsimile machine and thereceiving side facsimile machine are G3 facsimile machines categorizedbased on a T.30 Recommendation, the data-receiving control signalcomprises a data-receivable state confirmation signal CFR according tothe T.30 Recommendation, and the wait control signal comprises atransmission site identification signal TSI according to the T.30Recommendation.
 17. The program recording unit according to any ofclaims 12, wherein the transmission side facsimile machine and thereceiving side facsimile machine are G3 facsimile machines categorizedbased on a T.30 Recommendation, the data-receiving control signalcomprises a data-receivable state confirmation signal CFR according tothe T.30 Recommendation, and the wait control signal comprises atransmission site identification signal TSI according to the T.30Recommendation.
 18. The program recording unit according to any ofclaims 11, wherein the transmission side facsimile machine and thereceiving side facsimile machine are G3 facsimile machines categorizedbased on a T.30 Recommendation, the data-receiving control signalcomprises a data-receivable state confirmation signal CFR according tothe T.30 Recommendation, and the wait control signal comprises atransmission site identification signal TSI according to the T.30Recommendation.